.cel{
    width: 5em; height: 5em; 
    -webkit-border-radius: 5em; -moz-border-radius: 5em;
    text-align: center; margin-top: 4.5em;
    border:5px solid rgba(255, 0, 0, .5);
    margin-left: auto;
    margin-right: auto;
}

.newCel{
    position: absolute;
}

.ui-draggable-dragging{
	border:5px solid green;
}